Inclosed switch.



A. K. SUTHERLAND.

INCLOSED SWITCH,

APPLICATION FILED MA'R. 29,1918.

1,288,740. Patented Dec.24,1918. Y

INVENTOR time will be UNITED STATES PATENT OFFICE.

ALEXANDER K. SUTHERLAND, OF NEW BRITAIN, CONNECTICUT, ASSIGNOR TO THE TRUMBULL ELECTRIC MFG. CO., OEPLAINVILLE, CONNECTICUT, A CORPORATION OF CONNECTICUT.

. IN'CLOSED SWITCH.

Specification of Letters Patent.

Application filed March 29, 1918. Serial No. 225,446.

To all whom it may concern Be it known that I, ALEXANDER K. SUTH- nnnaxn, a subject of the King of Great Britain, residing at New Britain, Connect1- cut, have invented a new and useful Inclosed Switch, of which the following is a specification.

My present invention, as the title indicates, has reference to switches of the inclosed or so-called safety type, the general objects of the invention being to provide a switch of this character which will be relatively inexpensive and which at the same positive and certain in its operation.

Another important object is to provide automatic locking means for securing the cover closed when the switch is closed and for locking the switch open when the cover is open which will be simple, compact and not liable to g t out of order.

In the accomplishment of the foregoing and other objects, as will later appear, I employ a single locking member substantially 1n the form of a plate pivoted t rock into holding engagement with a locking shoulder carried by the operating handle and adapted tO-be released-from said locking shoulder by a stop on the cover, said locking plate being held interlocked with the cover stop when the cover is closed bv means of a cam element also carried by the operating handle.

Other features of the invention and details of construction will appear as the specification proceeds.

The accompanying drawing illustrates the invention as embodied in a practical commercial form, it being understood, however, that various changes and modifications may be made without departure from the true spirit and 'scope of the lnvention.

In said drawing: Figure 1 is a front view looking into an opened switch box having the invention incorporated therein, the switch in this being locked in the open circuit position.

Fig. 2 is a sectlonal view taken substantially on the plane 'of the line H of Fig.

1 and indicating the locking parts, in the position just described.

Fig. 3-is a similar sectional view on the line 23 showing the cover locked closed and the switch free to be operated.

Fig. 4 1s a cross sectional view of the handle construction;

The switch box or casing 5 is shown as made of sheet metal and provided with a hinged cover 6, as common in this art. The

switch 7 which is mounted in the box'may be of any approved construction and is shown as of the type disclosed in Patent No. 1,254,067 having a movable switch element 8 pivoted on the center 9.

10 designates the switch operating membe! Shown in the form of a handle journaled in the side wall of the box on a center corresponding to the pivotal center of the movable switch element.

A preferred form of mounting for the switch handle is shown in detail in Fig. 4,

the same consisting of a bearing disk 11 K which is rotatably seated in a journal opening provided therefor in the wall of the box, said bearing disk being of slightly thicker metal than the wall of the box, the handle 10 being. securednto. the outer face of this bearing disk, and a plate 13 being secured to the inner face of said bearing disk, said handle-and plate having portions extending beyond the rim of the bearingdisk so as t constitute abutments limiting the lateral shifting movement of the bearing disk in the journal opening. These parts may be secured together as by means of rivets 14 passed therethrough and there is shown a bracket 15 secured to the inner face of the plate 13, which bracket forms the operating connection between the handle locking-shoulder of the handle.

At the opposite side of the pivotal center 19 the locking member is slotted or forked to provide an abutment or jaw 21 and spaced above that a securing or holding projection or jaw 22, said upper securing jaw 22 being shown somewhat shorter than the lower abutment jaw 21', and the face of the abutment jaw being inclined somewhat on a downward slant from the outer or free end thereof.

Mounted on the cover in position to en' gage this lower inclined jaw is a stop or projection 23, shown in the form of an inwardly projecting pin carried by the dependent flange 24 of the cover. The edge of the box wall is slotted as indicated at 25 to admit this stop The locking plate is shown as acted upon by a spring 26 which rocks the plate forwardly to hold the hook portion of the plate either engaged with the locking shoulder of the handle as indicated in Fig. 2, or bearing upon the cam face 17 as indicated in Fig. 3. In the first condition referred to the switch is open and is locked in this open position by reason of engagement of the hook of the locking plate with the locking shoulder carried' by the handle. In this forwardly rocked condition of the locking plate the upper cover securing-j aw 22 is free of the locking pin on the cover, and the cover is then freed from the control of the automatic looking mechanism. IVhen the cover is closed, as shown in Fig. 3, the locking pin on the cover strikes the inclined face of the lower abutment jaw and rocks the locking plate in a direction to free t-he hook thereon from engagement with the] locking shoulder of the handle. In the course of this movement, it will be noted that the securing jaw. becomes engaged over the top of the locking 1 pin. The switch is now free to be shifted to vclosed circuit position. As soon as the 1 switch handle is rocked forwardly to close the circuit, the cam track 17' is brought be neath the nose of the locking plate,- and then acts as an abutment to prevent said locking plate from rocking forwardly so as to re.-

lease'the cover. This cam track thus operates to. hold the locking plate in securing engagement with the stop on the cover so long as'the switch is in closed circuit posi-- tion and up to the time that the switch has The locking plate may be mounted in a small casing 27 secured to the inne face of the box wall as bymeans of suitable fastenings such as the rivets 28. The bottom wall of this casing may serve as an abutment for the spring 26. A light spring 29 is shown provided for holding the locking plate shifted over againstthe sidewall of the box-into the plane of the cam diskof the handle. The locking plate is further shown provided with an abutment lug to take the thrust of the spring, which lug, as-

plainly appears'in Fig. 1, is angularly offset from the otherwise flat plane of the plate so as to provide room between the plate and the side of the box for the spring 26.

From the foregoing, the invention will be seen to possess many advantages in the way of general simplicity, ruggedness of structure, etc., and it will be apparent furthermore that the locking operation of the device is positive and sure.

I claim:

1. In combination, a switch casing having a movable cover, a switch in said casing having a movable switch element, a switch operating member journaled in one wall of the casing and provided with a stop shoulder, connections from said switch operating member to the movable switch element, a

hook pivoted on the casing adjacent the operating lever and arranged to engage the stop shoulder aforesaid, said hook'havinga slot therein and the casing having a slot in the wall thereof coinciding with said slot, and a locking abutment on the cover arranged as the cover is closed to pass mto the coinciding slots and rock the hook on its ed to drop into engagement with the locking shoulder to hold the switch in open circuit position, and means on the movable cover for engagement with the hook to rock the same out of engagement with the locldng shoulder of the cam. e

3. In combination, a switch casing having am'ova'ble cover,'a switch in said casing, a movable I switch operating member provided ,with a locking shoulder, a locking member provided with a stop shoulder for engage-- ment with the'locking shoulder to hold the switch operating'member in a predetermined position, a stop on the movable cover for engaging the'locking member in the closing movement of the cover to shift said locking -memb'er a-nd throw the stop shoulder thereon free of the locking shoulder, a securing pro jection on the locking member positioned to make interlocking engagement with the stop out of holding engagement with the locking shoulder, means on said locking member for engagement with the projection on the cover when shifted thereby to secure said cover projection, and means carried by the switch operating member for holding the pivoted locking member in position securing the pro jection on the cover.

5. In an inclosed switch, a switch box having a movable cover, a switch in said box, a pivotedswitch operating member provided with a locking shoulder, a pivoted locking member provided with a stop shoulder for engagement with the locking shoulder to hold the switch operating member in a predetermined position, a stop on the movable cover for engagement with the pivoted locking member to shift the same and throw the stop shoulder thereon out of engagement with the locking shoulder, a securing projection on the locking member arranged to be carried into securing engagement with the stop on the cover as the locking member is shifted by said stop, and a holding track on the operating member engageable with the locking member as said operating member is shifted after the release of the locking shoulder for holding the securing projection engaged with the stop on the cover. 6. In an inclosed switch, a switch box having a movable cover, a switch in said switch box, an operating handle journaled in the switch box, a locking shoulder carried by said operating handle and a cam track to one side of said locking shoulder, a locking member pivoted in the switch box having a stop shoulder for engagement with the locking shoulder, a stop on the movable cover engageable with the locking member to shift the stop shoulder thereon outof engagement with the locking shoulder and into position to be engaged by the holding cam when the operating andle 1s operated, and a securing pro ection on the locking member adapted to be engaged with the stop on the cover as said member is shifted by said stop and arranged to be held engaged with said stop by the holding cam aforesaid.

7. In an inclosed switch, a switch box having a movable cover, a switch insaid box, an operating handle journaled in the box and connected with the switch, a stop shoulder carried by said operating handle and a cam track at one side of said stop shoulder, a pivoted locking member having a stop shoulder at one side of the point of pivotal support for engagement with the locking shoulder, and spaced holding jaws'at the opposite side of the center of pivotal support, and a stop on the cover engageable between said spaced holding jaws to rock the stop shoulder out of 4 engagement with the locking shoulder, said locking member being engaged by the holding cam when the handle is then operated to hold the jaws aforesaid engaged with the stop on the cover.

8. In an inclosed switch, a switch box having a movable cover, a switch in said box, an operating handle journaled in the box and connected with the switch, a disk carried by said handle having a cam track terminating in an abrupt locking shoulder, a pivot-edlocking plate having a stop shoulder for engagement with the locking shoulder and a pair of spaced holding jaws, and a stop on the movable cover engageable with one of said jaws to rock said plate on its pivot and carry the stop shoulder out of engagement with the locking shoulder and the other jaw into position over the stop, said locking plate having a part engaged by the cam track when the handle is then operated to hold said last mentioned jaw engaged over the stop on the cover.

9. In an inclosed switch, a switch box having a slot cut in the edge of one of the side the box, a handle journaled in said side wall of the box and connected with the switch, a cam plate carried by said handle having a cam track for holding the locking plate rocked into position engaged with the cover projection and an abrupt locking shoulder at the end of said cam track, and a stop shoulder on the locking plate for engage ment with the locking shoulder.

ALEXANDER K. SUTHERLAND, 

